目的建立免疫富集联合基质辅助激光解吸电离飞行时间质谱法(matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF MS)检测牛奶、鸡蛋中沙门氏菌的方法。方法沙门氏菌经免疫磁珠特异性富集后采用MA...目的建立免疫富集联合基质辅助激光解吸电离飞行时间质谱法(matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF MS)检测牛奶、鸡蛋中沙门氏菌的方法。方法沙门氏菌经免疫磁珠特异性富集后采用MALDI-TOF MS鉴定,并优化富集过程中的抗体、免疫磁珠添加量以及捕获时间,研究其特异性,并用于实际样品中沙门氏菌的检测。结果富集过程最佳反应条件为:每1 mg磁珠中抗体添加量为250μg,1 mL菌样中免疫磁珠添加量为600μL,捕获时间为30 min,免疫磁珠捕获沙门氏菌具有特异性;用于检测牛奶和鸡蛋中的沙门氏菌时,将浓度为3 CFU/mL的沙门氏菌特异性富集后选择性增菌9h即可被MALDI-TOF MS准确鉴定。结论该方法具有选择性好,特异性高,耗时短,结果准确的优点,为食品中沙门氏菌的检测提供相关参考。展开更多
A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This ...A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This strain was capable of removing 500 mg phenol/L in liquid minimal medium by 99.6% within 9 h and metabolizing phenol at concentrations up to 1100 mg/L. DNA sequencing and homologous analysis of 16S rRNA gene identified PD12 to be an Acinetobacter sp. Polyvinyl alcohol （PVA） was used as a gel matrix to immobilize Acinetobacter sp. strain PDI2 by repeated freezing and thawing. The factors affecting phenol degradation of immobilized cells were investigated, and the results showed that the immobilized cells could tolerate a high phenol level and protected the bacteria against changes in temperature and pH. Storage stability and reusability tests revealed that the phenol degradation functions of immobilized cells were stable after reuse for 50 times or storing at 4℃ for 50 d. These results indicate that immobilized Acinetobacter sp. strain PD 12 possesses a good application potential in the treatment of phenol-containing wastewater.展开更多
文摘目的建立免疫富集联合基质辅助激光解吸电离飞行时间质谱法(matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF MS)检测牛奶、鸡蛋中沙门氏菌的方法。方法沙门氏菌经免疫磁珠特异性富集后采用MALDI-TOF MS鉴定,并优化富集过程中的抗体、免疫磁珠添加量以及捕获时间,研究其特异性,并用于实际样品中沙门氏菌的检测。结果富集过程最佳反应条件为:每1 mg磁珠中抗体添加量为250μg,1 mL菌样中免疫磁珠添加量为600μL,捕获时间为30 min,免疫磁珠捕获沙门氏菌具有特异性;用于检测牛奶和鸡蛋中的沙门氏菌时,将浓度为3 CFU/mL的沙门氏菌特异性富集后选择性增菌9h即可被MALDI-TOF MS准确鉴定。结论该方法具有选择性好,特异性高,耗时短,结果准确的优点,为食品中沙门氏菌的检测提供相关参考。
基金Project supported by the Undergraduate Research Foundation of Nankai University (2004).
文摘A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This strain was capable of removing 500 mg phenol/L in liquid minimal medium by 99.6% within 9 h and metabolizing phenol at concentrations up to 1100 mg/L. DNA sequencing and homologous analysis of 16S rRNA gene identified PD12 to be an Acinetobacter sp. Polyvinyl alcohol （PVA） was used as a gel matrix to immobilize Acinetobacter sp. strain PDI2 by repeated freezing and thawing. The factors affecting phenol degradation of immobilized cells were investigated, and the results showed that the immobilized cells could tolerate a high phenol level and protected the bacteria against changes in temperature and pH. Storage stability and reusability tests revealed that the phenol degradation functions of immobilized cells were stable after reuse for 50 times or storing at 4℃ for 50 d. These results indicate that immobilized Acinetobacter sp. strain PD 12 possesses a good application potential in the treatment of phenol-containing wastewater.
